Claude Opus 4.1 is an updated version of Anthropic’s flagship model, offering improved performance in coding, reasoning, and agentic tasks. It achieves 74.5% on SWE-bench Verified and shows notable gains in multi-file code refactoring, debu…
Model details →Anthropic: Claude Opus 4.1 vs OpenAI: GPT-5.3-Codex
OpenAI: GPT-5.3-Codex wins on 3 of 6 axes — pricing and capability skew in its favour for most workloads.
GPT-5.3-Codex is OpenAI’s most advanced agentic coding model, combining the frontier software engineering performance of GPT-5.2-Codex with the broader reasoning and professional knowledge capabilities of GPT-5.2. It achieves state-of-the-a…
Model details →Side-by-side comparison
| Capability | Anthropic: Claude Opus 4.1 | OpenAI: GPT-5.3-Codex | Winner |
|---|---|---|---|
| Context window Maximum number of input tokens the model can attend to in a single request. | 200K | 400K | 🏆 OpenAI: GPT-5.3-Codex |
| Input price (per 1M) Cost per million input tokens billed by the provider. | $15.00 | $1.75 | 🏆 OpenAI: GPT-5.3-Codex |
| Output price (per 1M) Cost per million output tokens billed by the provider. | $75.00 | $14.00 | 🏆 OpenAI: GPT-5.3-Codex |
| Tool / function calling First-class support for emitting structured tool calls. | Yes | Yes | Tie |
| Vision input Accepts image inputs alongside text. | Yes | Yes | Tie |
| Reasoning mode Internal chain-of-thought / extended-thinking support. | Yes | Yes | Tie |
Frequently asked questions
Is Anthropic: Claude Opus 4.1 better than OpenAI: GPT-5.3-Codex?
OpenAI: GPT-5.3-Codex wins on 3 of 6 axes — pricing and capability skew in its favour for most workloads.
What's the price difference between Anthropic: Claude Opus 4.1 and OpenAI: GPT-5.3-Codex?
Input: $15.00 vs $1.75 per 1M tokens. Output: $75.00 vs $14.00 per 1M tokens.
What context windows do Anthropic: Claude Opus 4.1 and OpenAI: GPT-5.3-Codex support?
Anthropic: Claude Opus 4.1 supports up to 200K tokens. OpenAI: GPT-5.3-Codex supports up to 400K tokens.
Do both Anthropic: Claude Opus 4.1 and OpenAI: GPT-5.3-Codex support tool calling?
Anthropic: Claude Opus 4.1: yes. OpenAI: GPT-5.3-Codex: yes.